Ffs guys, if you think 4 mil is way too much, just dont do it! Do not cry for nerfs just because you want to have same advantage some person, that actually put some effort (grinding 4mega xp) in it. Bullcrap.
Leave the levelling as it is, the grinders have anyways a uber advantage by the generational XP bonus, my mate is getting 1600xp/min on x1, i am getting 1200. I think that is OK. If he was able to retire more before, he has it easier to get to 31 now, by quite a big amount.
So stop whining, u wont get shinies without playing for them. Even from the RP point of view: you are being trained as a soldier for lvls 1-30, then ur training is somewhat done and u go plow your enemies. After some time doing this (lvl 30-31) you grow old enough to be released from the service, you slaughtered a lots of guys, you turned few tides, struggled during long time wars on battlefields.
Leave the retirement as it is, if you want to have an edge, work for it!
(and yeah, i work and shit, yet still i manage to make like 100-200k xp per day, gonna be more during free time
, still 3,3 mill away from 31, but i think its perfectly fine, i do not mind honing my skills with softcapped char till i get just some more to retire
)